RadiSys EXM-9 Reference page 20

4
Cyliner High Register
SDH Register
Status / Command Register
Floppy Operations Register
4
Floppy Command Register
Floppy Data Register
Alt. Status/Digital Output Register
Drive Address (IDE)/Floppy Control
The first two are standard EXM registers for device identification and configuration.
The EXM-9 responds to accesses to these ports only if EXMbus line -EXMID is
asserted. An 8-bit read from I/O address 100h returns the value F6, the device ID of
the EXM-9. A read/write configuration register appears at I/O address 102h. The de-
fined bits are as follows:
FLEN specifies whether the floppy diskette controller is enabled (1) or disabled (0).
If FLEN and CDEN are set, the I/O addresses 3F0-3F7 and the floppy diskette
controller are active.
IDEN specifies whether the IDE Interface is enabled (1) or disabled (0). If IDEN and
CDEN are set, the I/O addresses 1F0-1F7 and 3F6-3F7 are active.
CDEN specifies whether the EXM-9 is enabled (1) or disabled (0). If disabled, the
EXM-9 will not respond to the 1F0-1F7 and 3F0-3F7 I/O addresses; it will only
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EXM-9 Hardware Reference
1F6
1F7
3F2
3F4
3F5
3F6
3F7